In recent years, virtualization technology, which virtualizes a logical volume which is defined in one storage apparatus (hereinafter this will be called the first storage apparatus) in another storage apparatus (hereinafter this will be called the second storage apparatus) and which provides this virtualized logical volume to a host apparatus, has come into widespread use.
Furthermore, recent years have also witnessed the advent of computer systems which are designed to be able to a use such virtualization technology to virtualize a logical volume in a first storage apparatus by means of a plurality of second storage apparatuses and provide this logical volume to a plurality of host apparatuses. In such computer systems, one logical volume in this first storage apparatus can be shared by the plurality of host apparatuses.